Associations between eating disorder symptoms and latent bipolarity in patients with major depressive disorder.

Abstract

Objectives: To determine the correlations between eating disorder symptoms and clinical and psychometric characteristics of major depressive disorder (MDD).

Methods: Patients aged 18 to 59 years diagnosed with MDD, regardless of the stage (exacerbation or remission), were recruited from both outpatient and inpatient settings across seven centres in Russia. The MDD diagnosis of each patient was confirmed using the Mini International Neuropsychiatric Interview. Depression severity was assessed using the clinician-administered Montgomery-Asberg Depression Rating Scale. Disordered eating behaviours were assessed using the 26-item Eating Attitudes Test (EAT-26). Severity of anhedonia was assessed using the Snaith-Hamilton Pleasure Scale. Symptoms of hypomania were identified using the Hypomania Checklist. Suicide risk was assessed using the Columbia Suicide Severity Rating Scale. Symptoms of depression and anxiety were assessed using the Hospital Anxiety and Depression Scale. State and trait anxiety levels were assessed using the State-Trait Anxiety Inventory.

Results: In total, 216 women and 122 men aged 18 to 59 years with a diagnosis of MDD were included in analysis. Higher EAT-26 scores were associated with longer duration of the longest depressive episode, an earlier age of MDD onset, and a tendency towards hyperphagia during depressive episodes. EAT-26 scores were positively correlated with the Hypomania Checklist scores (ρ = 0.346, p < 0.001), the presence of suicidal ideations during the previous month (ρ = 0.146, p = 0.008), and the trait anxiety score (ρ = 0.198, p = 0.003) of the State-Trait Anxiety Inventory.

Conclusion: Patients with MDD who exhibited more pronounced disordered eating behaviours also had an earlier age of onset, a longer duration of the longest depressive episode, and higher Hypomania Checklist scores. These clinical markers are more characteristic of bipolar disorder, suggesting latent bipolarity or an increased risk of progression to bipolar disorder.